From U.S. Pat. No. 6,327,079 B1 there is known a surgical microscope having separate ocular systems for two observers wherein respective oculars may be pivoted or rotated about an optical axis of an objective lens of the microscope.
There is an increasing demand for superimposing an electronically generated image with an image generated with the optical beam path of such microscopes. A problem encountered in some conventional applications is a lack of correct registration of the light optically generated microscopic image with respect to the superimposed electronically generated image.